This invention relates generally to adjustable fastening devices, and in particular to an adjustable fastening device of the type comprising a rack and a slider, the latter being releasably lockable in any selected position on the former so that articles, or parts of an article, attached to these two major components of the device can be adjustably fastened to each other. The invention is more specifically directed to the improved construction of the slider for use in such adjustable fastening device.
The adjustable fastening devices of the type above defined have been used extensively on the waistbands of garments such as trousers, skirts and jackets to properly fit the same on the wearer. The slider of the adjustable fastening device as heretofore made includes a body typically comprising a top wall, a pair of side walls, and a pair of inwardly directed ledges along the bottom edges of the respective side walls. The slider body is mounted astride the rack so as to be slidable therealong as guided by the side walls and the bottom ledges.
According to this conventional slider construction, the slider is easy to loosen or to become displaced from its properly engaged position upon the rack even when the latter is worn to the slightest degree due to the use of the device over an extended length of time. The smooth functioning of the slider and rack assembly can then be no longer expected. It may also be worth mentioning that the top wall of the slider body is constituted of a relatively thin plate only and is rather insufficient in strength in consideration of the high stresses that will be exerted thereon in the use of the adjustable fastening device on garments or like articles.